The present invention relates to a battery charger for electric vehicles.
The use is known of battery chargers for electric vehicles, i.e., appliances that can be connected to the conventional power supply line and to the battery of an electric vehicle, to recharge the battery itself.
In particular, such battery chargers are able to convert an alternating voltage at input, supplied by the conventional power supply line, into a direct current at output.
More specifically, common battery chargers comprise a power unit able to supply the output voltage towards the battery, controlled by a respective electronic control unit.
In particular, the electronic control unit can be connected to the station of the vehicle by means of the conventional CAN (Controller Area Network) bus and generally comprises an interface of communication with the station itself able to receive predefined control signals.
The electronic control unit also comprises an internal control device, of the type e.g. of a DSP (Digital Signal Processor), able to interpret and convert the control signals coming from the vehicle station into control signals of the power unit.
In particular, the control device can simply command the switching on and off of the power unit, can regulate the power supplied by it or can perform test operations on the power unit itself.
As is known, the maximum output power of a battery charger is restricted by the maximum input current coming from the power supply line (generally not above 16 A).
Consequently, battery chargers of the conventional type are able to supply a maximum power between 3000 W and 3500 W, something that generally requires long battery recharge times of the electric vehicle.
To overcome this drawback, the simultaneous use is known of two battery chargers in parallel, supplied by the same phase or different phases of the power supply line. Alternatively, the use is known of a single battery charger having a power unit able to supply a greater power.
Nevertheless, such solutions are not without drawbacks either.
In particular, the use of two battery chargers in parallel necessarily involves a considerably high cost.
It is in fact known that in particular the power unit of a battery charger can be subject to failures and that, in this case, the entire damaged battery charger has to be replaced.
In particular, in the case of the use of a single battery charger with a power unit able to supply a greater output power, this would mean the impossibility of charging the vehicle until the battery charger itself had been replaced.
Furthermore, the use of two battery chargers in parallel means considerable overall dimensions.